Excelsior

Follow us on

james@excelsiorgroup.co.uk

07976 306 494

Tag Archive: sports science

  1. Dr Mike Joyner “Sport Science: Servant or Master?”

    Leave a Comment

    “Don’t get distracted by the latest and greatest”

    understanding sports science

    Dr Joyner presenting

    Said Dr Mike Joyner at the head of his 2nd seminar at GAIN. His talk covered four key questions we need to ask before implementing a new scientific find in our training, as well as interesting insights that he has found useful.

    In a discussion the evening before, Dr Joyner had revealed that “40% of medical evidence turns over every 15 years, but certain fundamentals don’t turn over”.  That means that every 15 years 40% of what was “evidence” changes!

    The fundamentals that are constant are: Don’t smoke; access to clean water; don’t get fat and be physically active amongst others.

    As coaches it is easy to get distracted by new things, and ignore the fundamentals. Similarly we may feel obliged to chuck out what is working because something new is found and published, even if that is later to be found false. (Naseem Taleb talks about this in Antifragile, he calls it neoism).

    4 questions we should ask of sports science

    Dr Joyner is an expert on athletic performance and is based at the Mayo clinic. His talk was extremely useful and was an example of critical thinking. (This is supposedly taught at Universities, but yet many recent graduates blindly regurgitate “facts” based on “research” without appearing to question it). Dr Joyner went through the following questions we should ask and gave examples of each.

    1. Is it measureable?

    Max Oxygen uptake is measurable. However in a laboratory setting research needs to show a 1-5% improvement for the study to be valid. If you win a 10km race by 1% you win by 100m! Coaches are often looking for the 0.1 -1% Science can explain the big picture, but it sometimes misses the detail and often the context.

    mcnamara fallacy

    McNamara’s fallacy

    In the Vietnam war the USA decided to try and measure winning by counting body bags of US troops versus the Viet Cong. This became known as “McNamara’s fallacy” where this became the focus of politicians rather than a meaningful political-military strategy (Assuming that anyone can actually “win” a war).

    1. Is it meaningful?

    There is a good correlation between a runner’s Lactate Threshold (LT) and their Marathon speed. Therefore LT is both measurable and meaningful for Marathon runners. (I have seen this extrapolated to Judoka who have been told to “improve their LT” by running on a treadmill more. Here the sports scientists were getting the tail to wag the dog).

    1. Is it actionable?
    sports science questions

    Bud Winter quote

    Referring to Bud Winter’s book “Relax and Win”, Dr Joyner said that relaxation is a trainable effect.  Therefore we can use it in our sessions.

    If you just turn your training sessions into exercises and suffering, you’re missing the point.”

    In swimming every turn counts, so it is important to work on each move in a meaningful way. If this (and the dive) are ignored or paid lip service to, then the performance will suffer.

    1. Is it durable?

    Dr Joyner showed a list of diets and the research that shows if they affect weight loss. Guess what? The Atkins diet, the Zone diet, weight watchers and the Ornish diet ALL work. They work IF they are followed. The problem is that the really restrictive diets that stop people living normally like eating as a family or choosing from a restaurant menu are simply unsustainable.

    Any training programme or new piece of research must be durable and last beyond 6 weeks (the length of many studies) in order for it to be effective in the long term. Think accumulation of training rather than blitzing.

    What sports science can do for us

    lactate threshold testing

    lactate threshold testing

    So after quite a critical look at some urban legends and poor examples, Dr Joyner then gave some examples of what we can learn mainly for endurance type activities (where his interests lie). Lactate Threshold in untrained subjects is about 60% of their maximum effort. In trained subjects it ranges from 75-90% of their max.

    LT is highly trainable. The increase in mitochondria means more pyruvate is oxidised and less is shunted to lactate. “Almost anything you do that has frequency, intensity and duration” will make a difference to your Vo2 max and LT. For example:

    • 3-5 minute repeats will help VO2 Max (see yesterday’s blog on The Volume Trap)
    • 200m repeats will help improve LT.

    Running economy in the other hand is highly variable (up to 30%) and it is unclear how trainable it is. (I always question the research on this: it is often done on treadmills and the “interventions” bear no resemblance to exercises that I do with runners to improve their technique. Conclusions are then drawn that it doesn’t work, rather than “we don’t know how to coach in a lab”.)

    Dr Joyner then looked at the recent attempt to run a sub 2 hours Marathon by Nike. What did they do to try and get this time? They looked at all the small factors added together. The course, the temperature, fuelling the runners, as well as manipulating the running economy with drafting, pacing and of course the shoes.

    What was interesting here was the effect of drafting (something cyclists in a peloton know) with 8% of the total energy cost of a 5km race coming from having to overcome wind resistance. In the 100m sprint this rises to 16%!

    Training in fasted state

    training fasted

    Trained fasted state every morning at GAIN

    Sports science can help us identify potential limits to human performance too. Much research has been conducted on training in a fasted stated. However, Dr Joyner made the point that so many gels are used nowadays that people rarely train in a truly fasted state.

    People can fatigue from having low glycogen in the muscles or from Neuroglycopenia  (Neuro= Brain, Glyco= Sugar, Penia =deficiency. So, low brain sugar). People who fast and go low on Carbohydrate (CHO) down regulate their enzymes. When they return to a normal diet, their enzymes are less able to process this food.

    The impression I got from this was that that maybe we should just try to eat normally. Especially when sprinting and doing high intensity exercise: you need CHO.

    The Scientific Process

    I haven’t really given Dr Joyner justice due to my poor notetaking and poor grasp of physiology. However, please take away the thoughts on questioning research and what you are measuring.

    I asked him at the end about “Science” which now seems to be only valid if published, versus the “scientific process” which we should all be doing as coaches wanting to improve our athletes’ performance.

    He mentioned the “Citizen science” project which is about sharing ideas that work and testing them.  I suggested we have an aide memoire or checklist to help us validate what we do or discard practices that are defunct.

    His final words were “A lot of sports scientists are just data acquisition people and analysers”. We were in agreement that it is what we do with this information with real people that counts.

    Further reading:

  2. 7 Sports Science Myths: Dr Michael Joyner (Mayo clinic)

    Leave a Comment

    GAIN reflections

    Sports science myths

    Dr Joyner and me at the track

    Dr Mike Joyner is a faculty member of the Mayo clinic specialising in human performance physiology.

    I met him early on the Wednesday morning when he was attempting to roll around on the floor and get up despite his very long levers.  What impressed me was his effort and concentration in attempting a new task, no matter how difficult.

    We then had a great conversation over breakfast about long term athlete development, fundamental tumbling skills and education for those from a less than ideal background.  Fuelled by his enthusiasm and some pancakes and coffee, I was primed to learn his thoughts on sports science.

    Here is a summary of his key points

    1. Lactic Acid Makes Me Sore. Lactic acid is removed in 40/50 minutes post exercise. Active recovery does help this process, but ALL lactic acid is gone within 24 hours. Soreness after training is due to muscle damage.
    2. Sports drink and glucose are necessary. There is no effect of glucose ingestion until after 60 minutes on steady state exercise. Longer duration bouts of exercise may require some. There are many different variables including; the duration and intensity of the bout factors, and the nutritional status before exercise.

    Most studies are conducted early in the morning when the athletes are fasted, so extrapolating this to afternoon exercise may be tenuous. The 2% reduction in bodyweight due to dehydration DOES impact performance, so hydration matters.  Rinsing out the mouth with sugar can affect performance positively: it is like “brain candy”.

    1. It must be genetic. Size is the obvious example where genetics matter (I would say gender matters more) but there are only a few examples of what Dr Joyner calls “O. Athletes” (Knockout).
    christian mccaffrey genetics

    Christian McCaffrey

    An example of breeding would be Christian McCaffrey (drafted by Carolina Panthers) whose dad was Ed McCaffrey (Giants, 49ers, Broncos) and his maternal grandfather was Dave Sime who was an Olympic silver medallist in the 100m in 1960.

    Otherwise, studies have found little evidence for a “talent gene” except for some with ACTN3 and ACE genotypes for speed. There is no evidence for gene testing in young people to “predict talent”.

    Dr Joyner said there is a lot of “lazy thinking” about genetics. He then showed a slide with the headline “There are more mile/ 1500m world record holders from Kansas than Kenya”!

    The DNA variables would need to explain: Energy systems, muscle fibre type, superior coordination, body composition, motivation, psychology and trainability.  They would NOT explain social factors.

    1. To stretch or not to stretch? There is a vast amount of evidence on this, and it is all contexts specific. I made the point that a lot of the studies are asking the wrong question. “Does stretching before exercise prevent injury?” and then tested on military recruits before doing a 20 mile route march with kit in boots. Stretching is obviously the least important factor in that context.

     

    1. Altitude Training. The 1968 Olympics played a key role in the development of this research as for the first time athletes would be competing at altitude on a big scale. There is a need to compare the short vs long term effects due to the initial reduction in training quality.

    Dr Joyner says the data on Live High- Train Low is “all over the place”. The long term effects of living at altitude are an increase in lung capacity. But, you have to keep the training quality up.  Those who used altitude training successfully did a lot of short intervals to maintain quality.

    Some key points he asked us to consider were:

    Beware of individual variation; more is not always better; give it time to work; beware of effects on intensity training and volume; recovery is sometimes affected due to a reduction in sleep quality.

    1. My programme is better than your programme! Dr Joyner showed a video clip of one of the Olympic middle distance races (forget which) where the top 3 finishers were very close. All 3 of those runners followed very different training programmes: high mileage or high intensity intervals and so on. Yet, all 3 were effective.

    The idea that one programme is inherently better than another is flawed. In strength training research it isn’t so much the number of sets vs reps it’s the training to failure that is important. As long as intensity is involved, gains will be made in strength.

    Dr Joyner then showed video clips from the “Miracles of Men” ESPN documentary of the Soviet Ice Hockey team doing some very basic “old school” training in a gym. The imagination and variety of exercises was novel but the players were working hard too. (This clip can also be seen in the Red Army documentary on Netflix).

    He also showed the clip of the La Sierra High School training programme of the 1960s

    and what 15 minutes a day can do to form the foundation that is lacking in today’s youth.

    1. Today’s athletes are better. More people are competing today, with better financial incentives, so records tend to fall. Doping has also had an impact on some performances too.

    However, some of yesteryear’s performances were pretty impressive. Don Lash, in the 1930s, set the 2 mile record of 8:58.4 on a weekly mileage total of 25 miles.

    This comparison of Andre DeGrass  vs Jesse Owens shows the difference in track and shoes between 1936 and 2011

    Dr Joyner also showed how innovation changed standard practices and protocols. Everyone knows about Dick Fosbury, but at the same time Debbie Brill, a 13 year old girl, was doing the same technique. Both of them were able to try this because of better landing surfaces on the other side of the bar.

    Summary

    In the discussion that followed Dr Joyner summarised with “Get kids out, have fun, spend time with good coaches”. (That sounds a lot like what we are trying to do at Excelsior ADC).

    This was a refreshing and engaging discussion, which I have only briefly touched upon. I spoke to Dr Joyner about academics preaching to each other from Ivory Towers without actually coming into contact with real people in the real world.  He said “That’s why I practice Medicine one day a week, so I stay in touch”.

    Next Up: Steve Myrland’s  “Coaching better every day” about creating a culture.

    Yesterday: GAIN overview and Vern Gambetta’s call to action

  3. What the academics are keeping from the public

    Leave a Comment

    “The average number of readers of a scientific paper is…”

    before the beginningSir Martin Rees in his book “Before the beginning: our universe and others” discusses science, evidence and why information fails to get through to the public (Answer at the bottom of the page).

    University undergraduates are told by their lecturers that they must reference academic journals and that they need to be current. Books are less relevant as they are “out of date”. Naseem Taleb in “Antifragile” (a book) calls this “neomania“: the obsession with something new.

    Rees has this to say about journals:

    But these journals- what scientists call ‘the literature’– are impenetrable to non-specialists.  They now just exist for archival purposes, largely unread even by researchers, who depend more on informal ‘reprints’, email and conference.”

    Does that ring a bell for coaches who are wading through articles?

    Information distortion

    In the age of the tweet, the soundbite and 24 hr rolling news coverage, Rees explains that information can get distorted. Ben Goldacre talks about this in “Bad Science” where he postulates that science gets bad coverage due to the media being dominated by humanities students.

    Rees (the cynic) says “the distortion is even greater because some sceintists (and some institutions) are far more effective than others in communicating and promoting their researches.

    In the pseudoscience world, have you ever wondered why “power” is often narrowly defined by the ability to be tested on a force platform? Answer: where does most of the research come from? Which researcher is on the board of the company that makes the force platform?

    This power “research” is then disseminated as gospel (negative results are rarely published in journals, skewing the system further).

    Even if we see a well designed study, Rees suggests we bear in mind what Francis Crick has to say “no theory should agree with all the data, because some of the date are sure to be wrong!”

    Why we should ask difficult questions

    Francis bacon on learningOf course, we get what we deserve.  Francis Bacon said this in “The advancement of learning” (1605).

    “For as knowledges are now delivered, there is a kind of a contract of error between the deliverer and the receiver; for he that delivereth knowledge desireth to deliver it in such form as may be best believed, and not as may be best examined; and he that receiveth knowledge desireth rather present satisfaction than expectant inquiry.”

    Steve Myrland says that we believe our own fallibility more than the person presenting to us and that “those parts of presentations that are most confusing to us tend to be the parts we question least.”

    This then allows the “expert” to carry on building up an awe inspiring reputation that remains unchallenged.

    I see this a lot in pseudoscience journals from the UKSCA and NSCA: academics who have less coaching experience than our local primary school teachers are given platforms to promote their unfounded theories. Unfortunately those of us who coach have little time to write, let alone look at the references to check the validity of their claims.

    Thanks to Dr Rob Frost for lending me the book.

    Further reading:

    Answer: 0.6! (cynically, Rees wondered whether this included the referee).

  4. Bad Science

    Leave a Comment

    High pulls vs cleans

    High pulls

    Triple extension in the high pulls

    I was asked on Tuesday by an athlete who is quite new to weight lifting why I would teach cleans which are quite complex, if high pulls also work the triple extension.
    The answer is that I have got a lot of time with this athlete, so can afford to work on his technique without sacrificing his work that will lead to strength and power development. The clean will then enable him to perform the jerks without using a rack.

    But, the question is an excellent one, and should be asked by Coaches before they do any exercise or series of techniques, instead of doing something because everyone else is doing it.

    • Some National Governing Bodies specifically want cleans coached – why? If time is limited, then
    • dumbbell cleans
    •  jump squats
    • wave squats
    •  high pulls

    are all useful alternatives for developing power.

    Ben Goldacre’s Bad Science column in The Guardian is a good read and is an example of how to examine wild claims and pseudo science. This type of objectivity is uncommon in a lot of Coaching practice.

    It is especially interesting to read how the over complication of diet has led to a new brand of celebrity nutritionists who are being discredited due to their lack of scientific underpinning.

    I keep telling coaches and athletes that they should look at what they are trying to achieve, and find tools that do that job most efficiently.

    However, many people become attached to the “magic exercise” or “magic food” and then reverse engineer its usefulness to match the aims.

    Further reading:

  5. Improper Application and Interpretation of Sports Science Statistics

    10 Comments

    Juking the Stats: Why not all “research” is valid

    The latest craze in competitive sport appears to be the use of data to aid understanding of, and improvement in sporting performance. This has resulted in a glut of material, each item claiming to have established some new result which may have useful implications in the development and performance of human athletes.

    There are often studies conducted with non-athletes as well, and the line between what could be considered medical research as opposed to what is known as sports science is not clearly defined.

    I should stress that my knowledge of the field of sports science is limited, the purpose of this article is to question the structure and findings of some typical articles.

    A typical paper in this field might take the following form:

    1) Design a study with some hypothesis of interest
    2) Collect data from subjects (fitness testing)
    3) Analyse the data to check for consistency with the hypothesis
    4) Draw conclusions.

     A good statistician should be able to perform multiple roles.

    In my opinion, some of the most important are:

    1. To decide on the real questions at the heart of a problem of interest, not to just churn out results for the sake of it.
    2.  To decide if a hypothesis is necessary, and if so to construct one which is of real actual interest. Sometimes it is best to approach a problem with an open mind, in the knowledge that there are likely to be interesting results, but unsure of what they will be.
    3. To employ appropriate methods (typically statistical models) to analyse the collected data (we don’t need to get too technical here).
    4. To explain the underlying reasons behind any results – studies in which results are simply quoted as gospel are of limited interest to me.
    5. To critically review the work, pointing out potential shortcomings and areas for future research.

    The final point is perhaps the most interesting. It is often the role of a statistician to dampen (or in some cases pour cold water) on enthusiasm about some exciting results.

    Sports Science Statistics must be taken in context.

    Conclusions drawn from a study of, say, a weightlifter’s improved performance due to a certain type of training programme should not be used as an automatic basis for a different strength-based sport, such as rowing.

    I work in the field of weather forecasting. A modern-day weather forecast involves running a computer model forward in time to produce a single forecast of the atmosphere. Statistics of this forecast (such as the average forecast error) can be calculated at different locations. It is well-known that such statistics vary by location – it is more difficult to predict the weather in Shetland than in the Sahara Desert. We could not, therefore, use statistics derived from one location to predict the average forecast error in another.

    In short, statistics is about describing what might have happened in a given context, but didn’t. We can use these findings to issue probabilities of what might happen in the future, on the basis that the context is consistent.

    Forget the weather: what about sport science?

    The few articles I have read in the sports science field (in all honesty I couldn’t face reading too many!) seem to fall short on many of the above points.

    For example, Owen et al. (J Strength Cond Res, 2011) conduct a study of heart rate responses of soccer players when playing in three-sided and nine-sided games. They conclude that the HR of players in three-sided games is consistently higher than for nine-sided games. They also note that three-sided games provide more shooting chances, and encourage players to run more with the ball, whilst the nine-sided games produced more tackles, passes and interceptions.

    They draw the conclusions that three-sided games are preferable for fitness training, and suggest that strikers should participate in three-sided games whilst defenders should concentrate on nine-sided games.

    I have two main problems with this work from both a scientific and practical viewpoint.

    1. The statistics quoted in themselves should be treated with caution, given the small sample size of fifteen players who participated in only a few games of each type. Without conducting a formal test I cannot be more precise, but these measurements are undoubtedly subject to substantial variation.
    2. What insight does the study really offer us? Aren’t the findings, on which the entire article is based, merely confirmation of the obvious? It is useful here to consider the so-called `pyramid of outcomes’ .

    This study gives only surrogate measures (the base of the pyramid), but assumes in the conclusion that such surrogates automatically extend in to true performance measures (essentially whether they can be used to increase the probability of winning football matches).

    This assumption seems completely without foundation when one considers the practical implications of the study. For example, suppose that on the basis of the study, strikers train in three-sided games whilst defenders train in nine-sided games, in order to provide more shooting opportunities for strikers and more defending opportunities for defenders. Is there really any point in this? Wouldn’t three-sided games just result in strikers shooting from anywhere, and playing (by definition) against less able defensive opposition? Surely the way to improve as a striker is to learn how to play against good defenders?

    Frankly, this work smacks of conducting a study for the sake of it, and drawing conclusions based on a few surrogate measurements without paying any attention to the sport of interest.

    How to conduct a more informative study.

    1) Collect a larger sample of players from a variety of clubs, preferably from different countries.
    2) Train different groups of players in different environments, as suggested by the study.
    3) Collect surrogate measurements from the different training sessions.
    4) Examine if the surrogates had an effect on actual game results (i.e. construct a proper statistical model rather than merely reporting surrogate values).
    5) Examine whether a return to previous training routines result in a reversion to previous performance.

    A statistical model is essentially the use of surrogate measurements to aid in predicting the value of, and assessing the uncertainty in, measurements at the top of the pyramid. The article mentioned here simply assumes that larger surrogate values immediately imply improved results, an assertion which is without foundation.

    Such a study would admittedly be hard to carry out both practically and from a theoretical statistical viewpoint. However, we are dealing with complicated situations – we are essentially trying to model outcomes from the human body, an immensely complicated organism.

    This is my overriding point, studies which simply churn out results for the sake of publishing papers are of little practical use. I would go further and suggest that they are actually dangerous in the wrong hands – a statistical model is no good in the hands of an incapable operator.

    Conclusion

    From my brief consultation of the literature, I have seen many examples of a mis-use of statistics which would not be permitted in a statistics journal.

    The typical methods used are likely to underestimate the complexity of the situation at hand. I suspect therefore, that the true value of statistics such as the p-value are somewhat larger than reported.

    I feel confident in ascerting that the conclusions of the articles I have read are based on extremely shaky ground in a theoretical sense, let alone their practical shortcomings.

    Robin Williams Statistics Phd Student (University of Exeter),  England Blind Footballer, 2012 Olympian

    More on interpretation of data here 

  6. An Accurate Observation Is Never Wrong or What a Coach Needs to Know: Thomas Kurz

    3 Comments

    Tom Kurz

    First a statement from James Marshall’s book review of my book “Science of Sports Training”

    “The book is a bit old now, published in 2001, with most of the research quoted pre-dating that. This would probably disqualify it from being used as an academic text book, but as a Coaching handbook it is very good.”

    This made me think:

    “How important really is for a coach to have the most up-to-date research?”

    I quoted a lot of research papers in this book and in my other books. I did it to back up claims or advice that run contrary to common wisdom (or rather common stupidity…).

    Some of the old research I quoted was, and still is valuable no matter whether it was done in 1920 or in 2000. Human physiology (including its expression in human psychology) doesn’t change from decade to decade, not from century to century, hardly from millennium to millennium, so accurate observations of human nature hold true no matter their age. (Think the oldest medical manuals of India and China, or fencing manuals of ages past….)

    Valuable studies and experiments are those that reveal truths not likely arrived at by “listening to one’s body” or “paying attention to clues.” Everything else is just fulfilling the academic requirement to publish.

    What is important for a coach?

    Understanding human body and mind enough to know the relation between input and output, then observing athletes and adjusting the input. In one of my blog posts Training vs Skill Training or More on Super Slow and Similar Approaches, I wrote: “When in doubt, refer to everyday observations. An accurate observation is never wrong.”

    Take the most important, in my opinion, principle of sports training: The Principle of Individualization and Accessibility of Training. (When you think of it, all other principles of training are based on that one.) If you apply it, you see that studying the most recent research on exercise science matters much less than observing:

    • athletes’ mood
    • movement quality
    • signs of fatigue
    • signs of apprehension

    and adjusting training process accordingly.

    More articles on the practical application of principles of training are here and my observation-based posts are in my blog .

    Tom Kurz is the author of “Science of Sports Training.”

    Further reading:

  7. Exercise Physiology: Understanding the athlete within

    3 Comments

    “The performance of elite athletes is likely to defy the types of easy explanations sought by scientific reductionism.” (1)

    exercise physiology courseThe weak chink in my coaching armour (or the weakest link amongst many) is my exercise physiology knowledge. Having studied Italian at school instead of biology, I avoided Exercise Physiology subjects when doing my MSc.

    My coaching has been mainly with team sport or combat athletes and I have never felt the need to know more than the basics of physiology.

    However, when this course came up on Coursera, I took the opportunity to rectify this and see if I could help my current crop of athletes that include cyclists, modern pentathletes, marathoners and 1500m runners.

    Course outline

    Mark Hargreaves of Melbourne University set up the course with the aim that at the end of the course I would be able to:

    •describe the sequence of events in muscle contraction, the characteristics of skeletal muscle fibre types, their recruitment during exercise and relevance to athletic performance, the sites of energy use during muscle contraction and the specific muscle adaptations to different types of exercise.

    •  summarise the energy systems utilized during exercise of varying intensity and duration and understand the factors that influence carbohydrate and fat metabolism during exercise.

    •  describe the cardiorespiratory responses to exercise that facilitate oxygen delivery to, and consumption by, contracting skeletal muscle during exercise and summarise the physiological determinants of maximal oxygen uptake.

    •  understand the mechanisms of heat loss during exercise and their physiological implications, the effect of heat stress on physiological and metabolic responses to exercise and effective countermeasures, the effects of fluid loss on physiological function and the benefits of fluid replacement during exercise.

    •  describe the central and peripheral factors that mediate fatigue during exercise of varying intensity and duration and the physiological determinants of sprinting and endurance performance.

    •  appreciate the potential role of genetic factors in mediating exercise performance and responses to exercise training.

    There was a good mix of video lectures and journal articles to read. A pdf study guide also summarised the week’s learning with a very handy glossary. The 6 week course was punctuated by fortnightly quizzes, which counted towards the final mark.

    seb baylis A written assignment based on a case study of a collapsed Iron Man triathlete just before the finish line was peer reviewed. This has caused some consternation from other students as the marking has appeared a bit random.

    I got 18/20 on this section (I was tempted to write that he probably collapsed from boredom having listened to his fellow triathletes talk about their training…).

    The final exam was 25 multiple choice questions, some of which were quite tough.

     Key lessons

    The relationship between exercise duration and intensity is responsible for what energy substrates are used. An increase in ambient temperature also has an impact, with more carbohydrate being used.

    Repeated sessions in the heat leads to Carbohydrate depletion. However, the major cause of fatigue in the heat is the rise of core body temperature above 38C. This impedes blood flow and together with a fall in blood pressure, impedes the ability of the cv system to function as effectively.

    Delaying or limiting the rise in core temperature can therefore improve performance in the heat: acclimatisation, pre-cooling and fluid ingestion being the three main ways.

    The relationship between local and central fatigue was covered in some depth. Referring to Tim Noakes’ Central Governor Theory, I understood it more now than I did 15 years ago when I first saw him present on it.

    Fatigue could be “mind over muscle” with the mind protecting the body from damaging itself. However, experience, emotions and motivation can all influence this relationship.

    A couple of definitions also helped me clarify my thoughts:

    “Fatigue is a reduction in force and poer generating capacity”.

    “Fatigue is an inability to maintain the required or expected force or power output.” (Task failure).

    The diaphragm appears to be a clever piece of human kit. As a major part of our respiratory system, it works hard during maximal exercise (up to 15% of VO2 is used by it. When it fatigues a reflex signal occurs to the working muscles which limits motor activation.

    The sporting champion will come from a genetic pool of elite athletes. But, they need to work hard and maximise opportunities given to them in order to prevail.

    Summary and thoughts

    blood cells The course went into some detail about the cellular actions and I am doubtful as to whether knowing that GLUT4 is a glucose transport protein will help me or my athletes.

    The cellular physiology was hard work for me, and I doubt if I will remember the details in a month’s time.

    I am struggling to think of one change to my coaching practice that I will make as a result of this course.

    I gained lots of information, but little wisdom. The knowledge may impact on what I do in the future. It may have helped me understand the theory underpinning my exisitng practice. I return to the opening quote: being a coach means there is more to performance than what happens in the cells.

    Saying that, the quality of the information, the design of the course and how it was structured mean that it did what it said on the tin. I will be able to use a lot of this information on the coaching courses I deliver.

    Thanks to Professor Hargreaves and his team for setting it up. 

    If you want some other ideas for courses see Anatomy and Physiology courses

    This was my 5th MOOC following:

    • Crash Course in Creativity
    • Data Visualisation and Infographics
    • How Things Work
    • Inspiring Leadership Through Emnotional Intelligence

    Next up: “From the Big Bang to Dark Energy” (way out of my confort zone).

    References

    1 Joyner, M, Coyle F. The Journal of Physiology  Volume 586, Issue 1pages 35–44, January 2008